Antimicrobial susceptibility patterns of ESBL Escherichia coli isolated from community and hospital-acquired urinary tract infections

Context: Increasing resistance of extended-spectrum β-lactamases (ESBL) producing bacteria is an important challenge for clinicians. Aims: Monitor the antibiotic susceptibility pattern of community and hospital acquired urinary tract infections (UTIs) caused by ESBL Escherichia coli. Settings and Design: This is a retrospective observational study that was conducted at a tertiary hospital in Riyadh. Materials and Methods: Results of urine culture with E. coli and their bacterial antimicrobial susceptibility were collected from patients' records for the years 2011 and 2012. When there was bacterial resistance to three groups of antibiotics, a multi-drug resistant (MDR) pattern was considered. Results: Of 3,967 patients with E. coli UTIs, 1,086 (27.4%) of patients had ESBL E. coli. Mean age of the study population in years was 39.1 (±28.8), 67.5% were females, and 32% were in the paediatric age group. The percentage of hospital-acquired ESBL E. coli was 64.5%, while outpatient-acquired was 35.5%. Overall, 75.1% of ESBL E. coli were resistant to trimethoprim/sulfamethoxazole, (69.8%) to ciprofloxacin and (40%) to gentamicin. However, high sensitivity to imipenem and meropenem was reported (99.8% each). Out of all the identified ESBL E. coli, MDR strains were identified in 137 (46%), and 161 (54%) isolates during the years 2011 and 2012, respectively. Conclusion: This study highlights the source and current antimicrobial susceptibility pattern of ESBL E. coli. Since bacterial multidrug resistance is an increasingly existing problem, periodical monitoring of antimicrobial susceptibility, rotating the use of effective antimicrobial drugs, and research for finding novel drugs and their rational use should be considered.